Republicanism is a political ideology that encompasses a range of ideas from civic virtue, political participation, harms of corruption, positives of mixed constitution, rule of law, and others. Historically, it emphasizes the idea of self-governance and ranges from the rule of a representative minority or aristocracy to popular sovereignty. It has had different definitions and interpretations which vary significantly based on historical context and methodological approach. In countries ruled by a monarch or similar ruler, or with a monarch whose role is primarily ceremonial such as the United Kingdom, republicanism is simply the wish to replace the hereditary monarchy by some form of elected republic.
Republicanism may also refer to the non-ideological scientific approach to politics and governance. As the republican thinker and second president of the United States John Adams stated in the introduction to his famous A Defense of the Constitutions of Government of the United States of America, the "science of politics is the science of social happiness" and a republic is the form of government arrived at when the science of politics is appropriately applied to the creation of a rationally designed government.